Fire latch for elevator doors



W. C. HEISLER FIRE LATCH FOR ELEVATOR DOORS Feb. 23, 1960 2 Sheets-Sheet 1 Filed Dec. 16, 1957 Feb. 23, 1960 w. c. HElsLER FIRE LATCH FOR ELEVATOR DOORS Filed nec. 1e, 1957 2 Sheets-Sheet 2 INVENTQR ATTORNEY United States Patent O FIRE LATCH FOR ELEvAroR DooRs A William C. Heisler, Clifton Heights, Pa., assignor to Guilbert, Incorporated, Philadelphia, Pa., a corporation of Pennsylvania Application December 16, 1957, Serial No. 702,930

5 Claims. (Cl. 189-48) This invention relates to tire latches for elevator doors, and more particularly to automatic latching mechanism eiective for retaining elevator doors and the like in locked condition upon the occurrence of an excessive temperature in the vicinity thereof.

Single doors and separable doors of the bi-parting counterbalanced type or of the counterweighted slidedown type have heretofore been employed on elevators and the like. Such doors are customarily provided with safety interlocks so that the door is maintained in closed and locked condition before the elevator can be moved with respect thereto and so that the door is retained in closed and locked condition until the elevator has stopped at the landing where the doors are located.

. In separable doors, also, it has heretofore been proposed-to employ safety astragals and to compress such astragals to some extent.

`In the event of a lire it is desirable to maintain the door in locked condition so that the door will not be open and provide an undesired air vent.

It is the principal object of the present invention to various modifications and changes can be made in the structure disclosed without departing from the spirit of the invention.

Like numerals refer to like parts throughout the several views.

The fire latch in accordance with the present invention includes as components an abutment such as a rigid hook which is mounted at any preferred location, -for example, at a xed top framing member at a location such as opening in the hatchway, on a single door, or on one of the doors of bi-parting doors, and a bolt movable into engagement with the hook, and mounted on a single door, at a fixed location such as the top framing member of an opening in the hatchway, or on the other of the doors of bi-parting doors. The bolt is normally spring pressed towards a position for locking engagement with the abutment but is restrained from movement by a fusible link.

Where bi-parting doors are employed with an astragal of compressible type an additional resilient positioning means for the doors is also advantageously employed.

Referring now more particularly to the drawings and merely for purposes of illustration, the lire latch is shown in a particular application to upper and lower vertically separable bi-parting doors 10 and 11.

The upper door 10 can be provided at each side with the customary chain hitch 12 for raising and lowering the door 10 by a chain or the like (not shown).

At each end of the door 11, a bracket 15 is provided and while the bracket 15 at one end is illustrated, the

` bracket 15 at the other end is of similar construction provide an improved character of fire latch suitable for use on single doors as well as doors of the bi-parting counterbalanced type or of the oounterweighted slide down type for locking the door or doors in a closed position in case of the occurrence of a tire.

It is a further object of the present invention to pro- I vide latching mechanism of the character aforesaid which can be quickly and easily installed on various types of doors now in use, and without interference with the safety interlocks now employed.

It is a further object of the present invention to provide an improved character of tire latch for bi-parting doors and with which positioning means is provided for compressing a safety astragal when necessary.

It is a further object of the present invention to provide a device of the character aforesaid in which the parts are relatively simple in construction and reliable and positive in operation when required.

Other objects and advantageous features of the invention will be apparent from the description and claims. y The nature and characteristic features of the invention will be more readily understood from the following description, taken in connection with the accompanying drawings forming part thereof, in which:

Figure 1 is a fragmentary view in elevation showing a pair of elevator doors with the re latch of the present invention applied thereto;

Fig. 2 is a horizontal sectional view taken approximately on the line 2-2 of Fig. 1;

Fig. 3 is a vertical sectional view taken approximately on the line 3--3 of Fig. 2,'and with the guide removed; and

Fig. 4 is a vertical sectional view taken approximately on the line 4-4 of Fig. 1, and showing the locking bolt in released position.

It should, of course, be understood that the description and drawings herein are illustrative merely, and that but of opposite hand.

The bracket 15 is preferably made as a malleable iron casting, and includes a body portion 16 from which a downwardly extending integral plate 17 extends. lThe plate 17 is secured to the side of the door 11 facing into the hatchway by bolts 18.

The body portion 16 of the bracket 15 has, extending upwardly ltherefrom, an arm 19, preferably of hook shape.

At each end of the door 10, a bracket 20 is provided and while the bracket 20 at one end is illustrated, the bracket Z0 at the other end is of similar construction but of opposite hand.

The bracket 20 is preferably made as a malleable iron casting and is provided with an integral horizontal plate 21 which is secured to the under side edge of the door 10 by bolts 22 extending through an interposed spacer block 23.

The bracket 20 is preferably provided with integral spaced horizontal sockets 24 and 25 with a vertical integral connecting portion 26 therebetween. The sockets 24 and 25 have alined horizontally disposed openings 27 and 28 with a liner 29 extending therebetween and terminating inwardly of the outer end :of the socket 25. Within the liner 29 a bolt 30 is provided for horizontal slidable movement.

Within the portion of the liner 29 in the socket 25 a coil spring 31 is provided and is normally maintained in compressed condition. For this purpose, the bolt 30 has extending therefrom, and through a slot 32 in the liner 29, a retaining arm 33. The socket 24 has a slot 24a therein for the passage of the arm 33 when released. The socket 25 has extending from the outer face thereof, and parallel to the arm 33, a retaining arm 34. The arms 33 and 34 have extending therebetween and in engagement therewith a fusible link 35 of any desired material, capable of melting at a predetermined temperature. The bolt 30 can also have extending therefrom and through the slot 32 in the liner 29 a positioning arm 33a for limiting the extended position of the bolt 30 upon rupture of the fusible link 35.

Patented Feb. 23, 1960- As illustrated in Fig. 3, a compressible astragal 36 may be provided, carried by one of the doors, such as the upper door 10, and engaging the upper marginal edge of the lower door 11. If such an astragal 36 is employed it may also be desirable, in order to limit the degree of compression thereof to provide at each end of the astragal 36, a bumper 37 of any suitable material, such as rubber, to limit the closing movement of the doors and 11. The bumper 37 is secured to the lo'wer edge face of the door 10 by bolts 38.

Where a compressible astragal 36 is employed, as well as in certain other types of installations, it is desirable to provide door positioning and retaining structure to properly position the doors 10 and 11 for positive engagement of the bolt 30 with the hooked arm 17.

One suitable form of retainer or latching device is illustrated as including a spear shaped tongue 40 secured to an upper edge of the body portion 16 of the bracket 15.

The bracket 20 has an integral upward extension 41 from which a horizontal plate 42 extends. The plate 42 has secured thereto a retainer 43 with a pair of resilient spring arms 44. The spring arms 44 include end portions 4S for engagement in recessed portions of the tongue 40 so that within a limited range of movement the retainer will tend to position the doors 10 and 11 with respect to each other so that as the astragal 36 is partially compressed and, at the same time, the hooked arm 19 for engagement by the bolt 30 upon release of the bolt 30 will retain the doors in closed position.

'I'he mode of operation will now be pointed out.

The doors 10 and 1l, in normal operation, will be opened and closed in the usual manner. Upon closing of the doors 10 and 11, the spring arms 44 by their engagement with the recessed portions of the tongue 40 will retain the -doors 10 and 11 at the desired position with respect to each other.

Ifv now, an excessive temperature is attained so that the fusible link 35 is ruptured or melted, the bolt 30 will be released and urged by the spring 31 horizontally in wardly to a position so that it extends below the hooked arm 19. Any tendency of the doors 10 and 11 to separate or open will be resisted by the engagement of the bolt 30 with the hooked arm 19. The astragal 36, if employed, by reason of its compressibility will aid in sealing the opening between the doors 10 and 11.

I claim:

1. A lire latch for elevator doors comprising two members one of which is movable with respect to the other and at least one of which is a door, at least one bracket secured to one of said members at a side margin thereof and having a receptacle portion, at least one second bracket secured to the other of said members at a corresponding side margin thereof, interengaging devices carried by said brackets positioning the contiguous edges of said members in predetermined meeting relation, said second bracket having mounted therein a bolt horizontally slidably movable into locking engagement with said receptacle portion ifor preventing relative movement of said members, a resilient device engaging said bolt and normally urging said bolt into locking engagement with nected respectively at spaced locations along said link to said second bracket and said bolt and holding said bolt against movement by said resilient device, and stop means for limiting the advance of said bolt by said resilient device.

2. A iire latch for biparting upper and lower vertically movable elevator doors comprising at least one bracket secured to the upper margin of the lower door at one side thereof and having a hooked arm, at least one second bracket secured to the lower margin of the upper door at a corresponding side thereof, interengaging devices carried by said brackets positioning the contiguous edges of said doors in predetermined meeting relation, said second bracket having mounted therein a bolt horizontally slidably movable into locking engagement with said hooked arm for preventing separation of said doors, a resilient device engaging said bolt and normally urging said bolt into locking engagement with said hooked arm, an elongated fusible link connected respectively at spaced locations along said link to lsaid second lbracket and said bolt and holding -said bolt against 'movement by said resilient device, and stop means on one of said brackets for limitingthe advance of 4said bolt by said resilient device.

3. A fire latch as defined in claim 2 in which said second bracket has a sleeve mounted therein in which said bolt is slidably mounted and within which said resilient member is disposed, and said stop lmeans also includes a stop pin carried by said bolt, and said second bracket has a portion for engagement by said pin to limit movement of said bolt to looking position.

4. A fire latch as deined in claim 2 in which said second bracket has a sleeve mounted therein, said bolt is slidably mounted in said sleeve and said resilient device is disposed in said sleeve, said sleeve has a longitudinal slot, a connector is provided connected to said bolt and extending through saidY slot to which said fusible link is connected, said bolt as a part of said stop means has a stop pin connected thereto and extending through said slot, and said second bracket has a portion for engagement by said stop pin to limit movement o-f said bolt to locking position.

5. Latching apparatus for elevator doors comprising two members one of which isV vertically movable with respect to the other to a closed position andl at least one of which is a door, interengaging latching devices on said members at at least one side margin thereof holding said members in closed relation, and interengageable members carried respectively by said irst members at a corresponding side margin thereof, a resilient device for urging one of said last members to engagement with the other, said' last members having an elongated fusible link for controlling the engagement thereof, and stop means for limiting the movement of said one of said last members by said resilient device.

Rupp ,-..v May 12, 1903 Peele Oct. 24, 1911 

